rragan 200 Report post Posted June 18, 2017 I had to do a projection using magnetic North. The iPhone Compass can be set to show either. Would changing the compass allow Cachly to do a projection using one or the other North? One or the other may be needed for a cache. Share this post Link to post Share on other sites
1 rragan 200 Report post Posted June 19, 2017 I just did an experiment and returned to find your note. As you say, the Compass plays no role. I was trying to project a final location and using 52° magnetic North was specified. Using Cachly project gives the right answer for true North but not magnetic. I looked up the local declination of 13.5 degrees and corrected the heading to 65° and got the correct answer. It would be wonderful if projection could let you choose true or magnetic for the heading but declination varies by location. If you could read out the compass and compare to GPS to get local declination for magnetic, that would be cool but I don't know if that is possible. I found a free Declination app so that will suffice for the rare case the CO wants. Magnetic North projection. 1 Nic Hubbard reacted to this Share this post Link to post Share on other sites
0 Nic Hubbard 642 Report post Posted June 19, 2017 The compass wouldn't affect the actual projection math. Can you show me the cache or explain more what you are meaning? Share this post Link to post Share on other sites
0 DerLakaiMS 8 Report post Posted June 19, 2017 I guess this is basically requires to calculate the deviation between the coordinate system and the magnetic north based on the current location, as done e.g. in http://www.geomag.nrcan.gc.ca/calc/mdcal-en.php Share this post Link to post Share on other sites
0 HikingSeal 7 Report post Posted July 17, 2017 Related to this issue, when projecting a waypoint, does Cachly use your current position or the cache coordinates? I see a selection a couple items up but I don't think that is related to projection. In addition to rragan's request for selection of magnetic vs true, I'd add a request to select "project from? current position or cache coordinates" Share this post Link to post Share on other sites
0 Bolling 99 Report post Posted July 17, 2017 1 hour ago, HikingSeal said: Related to this issue, when projecting a waypoint, does Cachly use your current position or the cache coordinates? I see a selection a couple items up but I don't think that is related to projection. In addition to rragan's request for selection of magnetic vs true, I'd add a request to select "project from? current position or cache coordinates" The Projection is from the grey coordinates in the add waypoint section. You can select a preset coordinates of manually enter any coordinates you want to. The Projection will be from these coordinates. The grey coordinates will turn red after you've calculated a Projection. Share this post Link to post Share on other sites
I had to do a projection using magnetic North. The iPhone Compass can be set to show either. Would changing the compass allow Cachly to do a projection using one or the other North? One or the other may be needed for a cache.
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